`CxxRecordSemanticsKind::ExplicitlyUnsafe` and `CxxRecordSemanticsKind::UnsafePointerMember` were never directly used, and those do not indicate semantics: they indicate safety of the type when used from Swift, which should be handled by another request `IsSafeUseOfCxxDecl` instead of `CxxRecordSemantics`.
Having `ExplicitlyUnsafe` and `UnsafePointerMember` as semantics indicators was problematic, for instance, for types that are move-only and store a pointer at the same time. Swift allowed the usage of these types (under the rules for `UnsafePointerMember` types) when move-only types are disabled, and did not apply the move-only attribute on such types when move-only types are enabled.
rdar://110644300
Eliminate the error message
error: global freestanding macros not yet supported in script mode
by implementing name lookup, type checking, and code emission for
freestanding macros. The key problem here is that, in script mode,
it is ambiguous whether a use of a freestanding macro is an expression
or a declaration. We parse as an expression (as we do within a
function body), which then gets wrapped in a top-level code
declaration.
Teach various parts of the compiler to look through a top-level code
declaration wrapping a macro expansion expression that is for a
declaration or code-item macro, e.g., by recording these for global
name lookup and treating their expansions as "auxiliary" declarations.
Fixes rdar://109699501.
Address a few related issues that affect local types and opaque result types within macros:
* Don't add local types or opaque types encountered while parsing the
arguments of a freestanding macro to the global list. When we do add
them, make sure we're adding them to the outermost source file so
they'll get seen later. This avoids trying to generate code for these
types, because they aren't supposed to be part of the program. Note
that a similar problem remains for arguments to attached macros, which
will need to be addressed with a more significant refactoring.
* When determining whether opaque types should be substituted within a
resilience domain, check the outermost source files rather than the exact
source file, otherwise we will end up with a mismatch in
argument-passing conventions.
* When delaying the type checking of functions that occur as part of a
macro expansion, make sure we record them in the outermost Swift source
file. Otherwise, we won't come back to them.
There is a common theme here of using AST state on the source file in
a manner that isn't ideal, and starts to break down with macros. In
these cases, we're relying on side effects from earlier phases
(parsing and type checking) to inform later phases, rather than
properly expressing the dependencies through requests.
Fixes rdar://110674997&110713264.
stated in the original source.
If an extension macro can introduce protocol conformances, macro expansion
will check which of those protocols already have a stated conformance in the
original source. The protocols that don't will be passed as arguments to
extension macro expansion, indicating to the macro that it should only add
conformances to those protocols.
I had to disable typo correction in one test case to get it to pass without
diagnosing a cycle as a result of Sendable checking. But that's OK, because:
- Sendable checking is prone to request cycles and needs to be redesigned
- Typo correction is turned off in production
This basically undoes 3da6fe9c0d, which in hindsight was wrong.
There were no other usages of TypeArrayView anywhere else except for
GenericSignature::getGenericParams(), and it was almost never what
you want, so callers had to convert back and forth to an ArrayRef.
Remove it.
Attribute @_silgen_name is today only allowed to be used on functions, this change allows usage on globals as well. The motivation for that is to be able to "forward declare" globals just like it's today possible to do with functions (for the cases where it's not practical or convenient to use a bridging header).
Separately, this change also adds a @_silgen_name(raw: ...) syntax, which simply avoids mangling the name (by using the \01 name prefix that LLVM uses). The motivation for that is to be able to reference the "magic Darwin linker symbols" that can be used to look up section bounds (in the current dylib/module) -- those symbols don't use the underscore prefix in their mangled names.
Per the clarification during the review thread, all properties with
init accessors (including those that do not initialize any underlying
storage) are part of the memberwise initializer.
ClangImporter can import some methods as throwing that `@objc` cannot generate. For instance, an imported Objective-C method with an error out parameter in an unconventional position can still be imported as throwing no matter its selector, but `@objc` can only generate an error out parameter in an unconventional position if the matching selector part consists of the word `error` or (for the first part) ends with `Error`. Detect and diagnose these situations.
Note that the tests do not cover all of the new diagnostics because some of these conditions (like the `Void` parameter) cause selector mismatches and others (like the owned error parameter) are representable in the compiler but cannot currently be imported. I have chosen to add these diagnostics anyway in case there is a corner case that I haven’t discovered.
Fixes rdar://110100071.
Reformatting everything now that we have `llvm` namespaces. I've
separated this from the main commit to help manage merge-conflicts and
for making it a bit easier to read the mega-patch.
This is phase-1 of switching from llvm::Optional to std::optional in the
next rebranch. llvm::Optional was removed from upstream LLVM, so we need
to migrate off rather soon. On Darwin, std::optional, and llvm::Optional
have the same layout, so we don't need to be as concerned about ABI
beyond the name mangling. `llvm::Optional` is only returned from one
function in
```
getStandardTypeSubst(StringRef TypeName,
bool allowConcurrencyManglings);
```
It's the return value, so it should not impact the mangling of the
function, and the layout is the same as `std::optional`, so it should be
mostly okay. This function doesn't appear to have users, and the ABI was
already broken 2 years ago for concurrency and no one seemed to notice
so this should be "okay".
I'm doing the migration incrementally so that folks working on main can
cherry-pick back to the release/5.9 branch. Once 5.9 is done and locked
away, then we can go through and finish the replacement. Since `None`
and `Optional` show up in contexts where they are not `llvm::None` and
`llvm::Optional`, I'm preparing the work now by going through and
removing the namespace unwrapping and making the `llvm` namespace
explicit. This should make it fairly mechanical to go through and
replace llvm::Optional with std::optional, and llvm::None with
std::nullopt. It's also a change that can be brought onto the
release/5.9 with minimal impact. This should be an NFC change.
When checking for the sendability in a call, use the sendability of the
original argument expressions rather than the parameter type, looking
through any implicit conversions that might remove `Sendable`.
Fixes rdar://110763694 / FB12343467.
